The industrialized world is becoming acutely conscious of energy consumed in industrial processes. Indeed, with the rising costs of energy and the depletion of means for producing energy, the general consuming public is actively involved in a crusade to eliminate waste in the consumption of energy. Thus home kitchens, as well as those in restaurants large and small, are resorting to the use of microwave powered ovens, not only for the speed of food preparation, but because the overall power consumption of microwave ovens is significantly less than that required by conventional electrical resistance heated ovens. Those skilled in the art of heating by microwave radiation have been adapt at applying the advantages of this heating technique to processes other than that of food preparation.
In U.S. Pat. No. 3,585,258, issued June 15, 1971, Levinson teaches that a microwave source may be used to heat a mass of lossy material, which lossy material in turn provides a heat source within a kiln whereby wet clay objects may be fired.
An article, such as a plate or a bowl, may be directly heated with microwave energy if the article is manufactured in accordance with the disclosure provided by Sutton et al in U.S. Pat. No. 4,219,361 issued Aug. 26, 1980. Sutton et al teaches that an article may be made of materials which are not normally susceptible to heating by means of microwave energy if the basic material of which the article is comprised is first mixed with another material which is susceptible to heating by microwave energy radiation. The disclosure teaches that the following materials may be added to the basic material to make it susceptible to heating by microwave energy: cobalt oxide, chromium nitride, iron oxide, manganese dioxide, nickelous oxide, nickelic oxide, and calcium aluminate. The mixture of compounds susceptible to heating by microwave and those which display no such susceptibility remain a mixture within the final article produced, there being no chemical reaction taking place between the materials.
Bardet, in U.S. Pat. No. 4,100,386 issued July 11, 1978, teaches that a ceramic or refractory material, not normally susceptible to heating by microwave energy, may be melted when placed within a microwave cavity in close proximity to a probe made of a lossy material. The lossy material causes an increase in temperature at the proximate end of the ceramic material. Further, the electromagnetic field within the cavity is increased at this point due to the insertion and heating of the lossy material probe. The heating of the lossy probe causes the ceramic material to likewise experience a rise in temperature. As its temperature rises, the dielectric constant and the loss tangent of the ceramic material increases which in turn increases its susceptibility to heating by the impinging electromagnetic field. A point is soon reached at which the lossy probe may be removed and the heating of the ceramic material will continue apace until melting of the ceramic material occurs. Bardet discloses the melting of a pure silica bar of material and the drawing therefrom of a continuous thread of silica.
The process of Sutton et al, noted above, is brought to mind by the disclosure of Nishitani in U.S. Pat. No. 4,147,911. Nishitani's disclosure is directed toward the sintering of refractory materials, sintering being defined as the forming of a solid by compacting a powder and heating same below the melting point of the powdered material for several hours. A solid form then results. Nishitani finds that the process may be expedited by the inclusion of metallic particles within the refractory material. However, the conductive materials must first be micro-pulverized so that the conductive particles are no greater than ten times the skin depth of penetration of the microwave energy impinging on the refractory material. Heating of both the refractory material and the micro-pulverized conductive particles thus takes place due to the reaction of the conductive particles with the microwave field.
Another patent concerning the sintering of ceramic materials is that of Lacombe-Allard in U.S. Pat. No. 4,057,702 issued Nov. 8, 1977. Lacombe-Allard acknowledges the fact that ceramic materials and, in particular, refractory oxides may be made susceptible to heating under the influence of microwave energy by the incorporation within the ceramic composition of additives which are rapidly heated under the influence of an electromagnetic field. However, certain disadvantages of this approach are pointed out by Lacombe-Allard. He notes that the rise in temperature of the ceramic composition is initially very slow giving as an example that three-quarters of the total time of the operation may be required to raise the product to be sintered to a temperature which is less than one-half the sintering temperature. He notes further that special precautions must be taken to ensure homogenous heating of the products to be sintered and to control a rapid increase in the heating action as the sintering temperature is approached. In addition, the supports on which such ceramic material is emplaced in the microwave field are often susceptible to excessive heating which may affect the uniformity of heating of the ceramic material being sintered. To avoid these problems, Lacombe-Allard teaches that the refractory materials should be raised in temperature using conventional heating means prior to being introduced to the electromagnetic field radiated by the microwave source. By raising the temperature of the refractory materials, their dielectric constant and loss tangent are increased so that when they are exposed to the microwave radiation, they are susceptible to heating thereby and are rapidly brought to the sintering temperature. Thus, the disadvantages of additives to the basic refractory material are avoided.
All of the known art, as cited above, is directed toward the principle that a material which is not susceptible to heating by exposure to microwave radiation may have its temperature raised by placing it in close proximity to a material which is susceptible to such heating. The suceptible material is chosen for its susceptibility to heating upon exposure to microwave radiation and for its lack of reaction with the nonsusceptible material. None of the known prior art teaches that microwave energy radiation may be employed to bring about a chemical reaction between two or more reactants.
It is therefore an objective of the present invention to provide means and method for utilizing microwave radiation to being about a chemical reaction of two or more reactants radiated by an electromagnetic radio field.
It is a specific objective of the invention to provide means and method for utilizing a microwave energy source as the source of the electromagnetic radiation for bringing about the chemical reaction of two or more reactants.
It is a particular objective of the invention to provide means and method for utilizing electromagnetic radiation in the production of carbide.
It is a most specific objective of the invention to provide means and method for utilizing electromagnetic radiation in cooperation with an electrolysis process for causing the chemical reaction of two or more reactants.